Recently, the developments of the flat-panel display have matured. Under the promotion of the market, many companies and research units engage in the developments of the display device of the electronic paper. The display device of the electronic paper has the advantages of low power cost, portable convenience, being rolled up and no limitation of the visual angle. The material used for the display device of the electronic paper can be divided into the electrophoretic display material, the electrochromic display material and the twist ball display material. The electrophoresis is formed by charged particles spreading in the suspension solution, and the motion of charged particles can be controlled by applying the electric field to display desired images. Since the particles would influence the reflection of light, the conventional electrophoretic display device only can provide single color display, but not full color display.
New types of electrophoretic display devices provide a color ink layer to solve the problem of not being displayed in full color. According to U.S. Pat. No. 6,228,543 B1, a color photo resist layer can be transferred to an electrophoretic layer through thermal transfer.
Please refer to FIG. 1(a), which shows the conventional thermal transfer structure. The conventional thermal transfer structure 10 comprises a donor substrate 102, a light to heat conversion layer 104 and a color ink layer 106.
Please refer to FIG. 1(b), which shows that the conventional thermal transfer structure is irradiated. The irradiated thermal transfer structure 11 comprises a donor substrate 102, a light to heat conversion layer 104, a color ink layer 106 and an acceptor substrate 118. The light to heat conversion layer 104 typically comprises an irradiation absorbent body (not shown), which can absorb irradiation 110, such as laser beams. When the irradiation 110 illuminates at the light to heat conversion layer 104, the light to heat conversion layer 104 absorbs the irradiation 110 and converts a part of the absorbed irradiation 110 into heat to make the color ink layer 106 absorb the heat which is then transferred to the acceptor substrate 118, such as an electrophoretic layer.
Please refer to FIG. 1(c), which shows the conventional thermal transfer structure after transferred. After transferred, the thermal transfer structure 12 comprises a donor substrate 102, a light to heat conversion layer 104, a color ink layer 106 and an acceptor substrate 118. From FIG. 1(c), it is known that the color ink layer 106 has been transferred to the acceptor substrate 118, and the light to heat conversion layer 104 has been separated from the color ink layer 106.
Although the color ink layer 106 would adhere to the acceptor substrate 118 after thermal transfer, it will be easy to peel due to a poor adhesive force.